Micronodular Kaposi's sarcoma - a new variant of classic-sporadic Kaposi's sarcoma

Area of Science:

• Oncology
• Dermatology
• Virology

Background:

• Kaposi's sarcoma (KS) is a rare vascular neoplasm, typically affecting elderly men, and is etiologically linked to Human Herpesvirus 8 (HHV-8).
• Classic-sporadic KS predominantly affects men of Jewish or Mediterranean origin, presenting as brownish lesions on the lower legs.
• KS is rarely observed in women and typically presents differently than in men.

Observation:

• A 51-year-old, HIV-seronegative Caucasian woman presented with an unusual variant of KS.
• The variant manifested as small, scattered, firm red papules on her right arm, differing from typical KS presentations.
• Histology confirmed a nodular spindle cell tumor expressing endothelial markers, with evidence of HHV-8 antibodies and viral nucleic acids.

Findings:

• The diagnosis of the nodular stage of KS was confirmed through histological and serological markers.
• The patient experienced an indolent course with seasonal recurrences over 9 years, despite surgical and cryosurgical treatments.
• This presentation represents a previously undescribed clinical variant of KS.

Implications:

• The term 'micronodular KS' is proposed for this distinct clinical variant.
• This variant mimics capillary hemangioma, highlighting the diverse clinical spectrum of KS.
• Understanding this variant is crucial for accurate diagnosis and management of rare KS cases.